The present invention relates to the use of acylated benzilic acid derivatives in the form of N-alkyl-4-piperidyl .alpha.,.alpha.-diphenyl-.alpha.-acyloxyacetates for therapeutic purposes. It also relates to novel benzilic acid derivatives.
Numerous substances which are based on .alpha.,.alpha.-diphenylacetic acids and which have found use in pharmacotherapy as neurotropic or myotropic spasmolytics have been described. However, a selective effect of these substances specifically on the tone of the urinary bladder has not hitherto been satisfactorily demonstrated. Only the etherified derivative propiverine (1-methyl-4-piperidyl .alpha.,.alpha.-diphenyl-.alpha.-(n-propoxy)acetate) has shown therapeutic utility for this purpose (Zbl. Pharm. 120 (1981), 12, pages 1219-1224). However, this compound is insuficiently effective in some patients and is not amenable to general use because of certain side effects. Moreover, the hydrophobic nature of the compound results in diminished selectivity in the target area of the urinary bladder.
Furthermore, the large intrinsic myotropic/spasmolytic effect of parasympatholytic compounds hitherto used not uncommonly brings about inadequate contraction of the bladder muscle in the urinary bladder on active micturition, with the risk of the formation of residual urine.
The lowering of the blood pressure as has been described for therapy with propiverine (M. Blau, U. Retzke, Zbl. Gynakol. 100 (1984), 14, pages 981-987) may be regarded as another disadvantage of a pronounced myotropic/spasmolytic activity.